How to Calculate LCM
What is LCM?
The Least Common Multiple (LCM) is the smallest positive integer divisible by two or more given numbers. Used for adding fractions with different denominators, scheduling problems, and finding repeating patterns.
Step-by-Step Guide
- 1LCM(a,b) = |a × b| / GCF(a,b)
- 2Prime factorization: take all prime factors with highest powers
- 3LCM(4,6) = 12 → 4=2², 6=2×3, LCM = 2²×3 = 12
- 4LCM of coprime numbers (GCF=1) = their product
Worked Examples
Input
LCM(4, 6)
Result
12
Smallest number divisible by both 4 and 6
Input
LCM(12, 18, 24)
Result
72
Used to add 1/12 + 1/18 + 1/24
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